Piston



H. H. MEYER PISTON May 3 Filed Feb. 28,. 1924 INVENTOR. V BY LATT.ORNEY.

Iatented May 3, 1932?,

UNITED STATES ,PATENT: OFFI CEQ HENRY II. MEYER, or nmnorr, MICHIGAN.

PISTON.

Application filed February 28, 1924. Serial No. 695,642.

siderable extent from their normal shape to get them adjusted toposition tin the ring grooves on the piston. An object of nyirnprovements is to avoid the necessity of (hstorting the rings.-Another object is to se cure improved packing rings. T secure theseobjects, among others, by the 1neans illus Lrated in the accompanyingdrawing in which: v

Figure 1 is a vertical section of a piston ernbodying 1ny invention,also showing a portion of the adjacent walls of the cylinder.

Fig. 2 is a section on the line lI, H, Fig. l.

Fig.'3 is an elevation of the piston.

, Fig. 4 is a perspective view of one of the packing rings.

Fig. 5 is a perspective view of another of said packing rings.

Fig. 6 is a detail section showing a modi lied construction.

(L indicates the cylinder walls.

The piston is made up of two parts: the lower, Z), and the upper c. Thelower portion I) en1bodies the skirting and the bearings for the pistonpin. The upper part c forms the lower wall of the combustion cha1nber.The packing rings are held be tween the two portions, Z) and c. A

Z) is an annular charnber cored in the part b, and serving to retard theflow of heat through the same. Said chamber extending above the bearingsfor the piston pin. b" is a circular opening coaxial with the part bthrough the upper horizontal wall there of. The part 0 of the piston isprovided with a cylindrical screwtlnreaded projection c extendedvertically downward from the center thereof and passing through theaperture 7)*". is a nut, the threads of which engagc with the threads ofthe projection 0 b is an annular groove coaxial with the part Z) andexteruling into the upper surface thereof'. L indicates partial, orinterrupted, screw threads, (preferalt ly 4), in the outer wall of thegroove ZP. c is an annular projection coaxial with the part c of thepiston, adapted totit into the groove b in the part 7), and havingpartial, or interrupted, screw threads, o, adapted to pass downwardbetween the ends of the partial thread Z), and engage by a relativeangular down ward motion with their upper surfaces against the undersurfaees ofthe threads Z) 0 is a cylindrical wall coaxial With the partc, of less diaineter than said part and extending therefrorn. cisan'annular chamber cored out in the part c, and c" is a similareharnber cored out in the projection c These Chambers serve tointerruptthe flow of heat through the part 0, and to pro tect the engagingsurfaces of the partial thread, c Z') from the effects of high temperature and prevents the carbonization of the oil.

d is. a packing.ring having-the annular projection cl extending from theCenter ot its outer surface. d and d are complementary packingringsshapedto engage against the outer surface of the ringd, and toengage between them the annular projection (Z as shown.

is a conical surface extending around the upper end of the part b. (Z isa split ring resting upon the surface ZJ and hav ing its under surfaceshaped thereto.

All the above rings are of the usual elastic split-ring type.

The method of assembling the above described device is as follows, theparts b and c being separate The ring d is placed upon the conicalsurface Z) The rings d, (Z and (,Z, are then arranged as shown in Fig.1, and placed upon the upper horizontal surface of the ring (Z The partc is then adjusted to position, the annular projection, c passing intothe groove Z). The part 0 is then turned relative to the part 7), sothat the in clined upper surfaces of the partial threads, 0*, shallengage under the partial. threads, Z) and thus secure the part c fir1nlyin place, the shoulder o engaging o"er the upper surfaces of the rings,(Z, (Z The nut 0 is then screwed into position and set up tightly tohold the whole in place.

Of course, the rings, (Z, cZ-'*, (Z may be placed upon the part c aroundthe cylin drical wall, c, and engaging the shoulder, 0 before the partsare put in position, if desired. r

Instead of the surface Z) having straight elements in cross section,these may be curved and the ring fitted to it, as shown at b. (Z Fig. 6.

What I claim is 1. In a piston, the combination of an upper and a lowerpart having adj acent ends and having a ring groove between said parts,an annular groove extending into one of said ends within its periphery,an annular projection from the,other of said ends adapt ed to extendinto said groove and engaging serew threads on said projeetion and wallot said groove.

2. In a piston, the combination ot an upper and a lower part havingadjacent ends and having a ring groove between said parts, an annulargroove extending into one ot said ends within its periphery, an annuiarprojection front the other of said ends adapted to extend into saidgroove and engaging screw threads on said projection and wall of saidgroove, said projection being eored out to form a heatohstruotingehamber.

3. In a piston, the combination of an upper and a lower part havingadjacent ends and having a ring groove between them, an an nui-ar grooveextending into one of said ends within its periphery, an annuiarprojection from the other of said ends adapted to extend into saidgroove, and partial screw threads on said projection and a wall of saidgroove adapted to permit said projeetion to pass into said groove and toengage said parts together by a relative angular movement of the same.

et. In a piston, the combination of an upper and a lower part having aring groove between them, an annular groove in the surtaee of one ofsaid parts, an annuiar projeetion in the surface of the other ot saidpars adapted to pass into said groove and engaging cam threads inadjacent walls of said groove and said projection, an aperture throughthe upper wall of one ot said parts, a serewthreaded projeetion from theother ot said parts passing through said aperture and a nut upon the endot said projection.

5. 111 a piston, the combination ot two parts separate from each otherand adapted to be removably engaged and to hold the packing rings inproper position between said parts, the engagement between said partsbeing within the inner surface of said rings, the upper part o saidpiston being eored out to form a heatobstructing eham ber between saidengaging means and the heat-receiving surface of said part.

In testimony whereot, I sign this speci .tication.

HENRY H. MEYER.

